Gage.



J. ERSKINE.

GAGE.

APPLlcATxoN FILED Aue.27.1911.

Patented Feb. 25, 1919.

@Uttar/M4414 l 'X I 0,., 4 v M A-V. OF ELIN'T, MCHIGN, ASSIGNGR T0 GENERAL lIGTORS CRPORATION, 0F DETRET, HIGHEGAN, it` CGRPORATON QF DELAWARE. v

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GAGE

mesme.

Bpecillc'ation of Letters Patent. Patented Feb, 25, 1919. y

' Application filed August 27, 1917. Serial No. 188,370.

To all whom it may concern.' Be it known that l, JAMES Resume, a citizen of the United `States of America, residl.

-v my gage in connection with the propelling pump of an engineflubricating system;

Fig 2 is a sectional elevation of the gage; l

and

Fig. 3 is a-horizontal section therethrough. In the present state of the art various gages have been devised which operate by the positive ressure developed by the lubricant pump, t is pressure' being usually coinmunicated to the indicator by air. @ne ob- 'jection to such constructions is that where i' there is any clogging or stoppage of the lubricant While the pump is still in operation the pressure may rise to a point whereit will force lubricant into the gage or indicator. l have avoided this difficulty by operating my improved gage or indicator from the suction side ofthe pump, so that there cannever be any discharge of lubricant at the indicator. Asl shown, A is the crank case of an engine, B the oil-well therein, Ca lubricating pump, shown as of the intermeshing-gear type, D the discharge conduit from said pump and E the suction conduit thereof, F is my improved' gage or indicator, which comprises a cylindei-G with a slidable piston H therein and'l an indicator I attached to the piston. The cylinder G is connected by a conduit J With the pump, said conduit extending in to the suction conduit E, as shown. Thus when the pump is in operation air will be drawn out from the conduit J into the liquid in the pump, causing the piston H to rise by atmospheric pressure and display the indicator I. Suiiicient clearance lis' provided between the piston and cylinder to vpermit a slight leakage of air, so that whenever the flow of lubricant through the suction conduit is' arrested the air pressurev within the cylinder Iwill equalize that wit-hout, and the piston and indicator will drop.

it is obvioustliat with this construction thereccan be no danger of discharging the lubricant in to .the indicator, as the flow is in the reversedirection. vOn the other hand,

a positive indication ofthe flow oflubi'icanty a falling in the flowy beyond a predetermined y point will observed on the indicator.y Under certain conditions, such for instance as the freezing of Water which is mixed with the oil, there muy be a stoppage in the lubricant circulating system, which if the pump continues to' operate is dangerous. I thereforel have provide such a condition, which as shown consists means. for indicating of a weighted stop li, which arrests movement of the piston and indicator under nor- .nial conditions and which will 'be lifted to. display a danger signal under abnormal conf ditions. it is obvious that if there is a stoppage whichprevents How of oil through the suction conduit E, a high vacuum will'be formed which, reacting upon the conduit J sov and cylinder G, will'lift the piston and' weight L. y

V'io reduce an inexpensive construction to manu ecture and one easily assembled, my. e

gage' is preferably specifically construct'e as follows. The cylinder Gr is formed with a laterallyfextending nipple, G/Which passesl through the back cfa cup-shaped housing ivi and is adapted'to engagea cou ling N for the securing of the conduit J. F'lhe indicator l has an angle shank I' attaching to the lower end of the piston, and the weighted stop L is sleeved upon the cylinder and lies adiacent to the indicator. 0 is a ringadapted for mounting upon the vehicle dash or other pointcf support. P is a glassv face held by the ring and Q is an opaque dish adjacent to the glass having a slot Q -therein through which the signal is displayed. Tlie ring O has a cylindrical iiaiige G for receivingl the cupshaped member M and the parts after engagement are locked' py a spring R Within'tle housing, having its opposite. ends engaging registering apertures 1n the member M and lange O. All of the circular parts may be held in proper registration by providing` a slotl (c)2 in the flange O with which is engaged projecting lugs Q2 and M on the members Q and IVI respectively.

In operation, when the pump is idle, as long` as oil is not iowing through the suction conduit, the piston II will drop to the bottom indicator with it7 until the shank I comes in Contact with the weighted stop Under normal conditions the suction is insuilicient to lift this weight and therefore the indicator will be in a position to display the word On, or other indication that'the woil is cifulating. If, however, there is an abnormal condition, previously described, the

suction will lift the weight which will'more the indicator to a position displaying the word 'Danger. y

What I claim as my invention is:

l.. The combination with a liquid-circulating.;` system and a hydraulic pump for actuating the same, of a pneumatically-operated gage for indicatingconditions in said system, and a connection between said 'indicator and the suction conduit of said pump transmitting; to the gage a suba-tmospheric pressure created by the pump.

2. rIhe combination with a liquid-circulat- 'mg system, ot' means for creating a subatmospheric'pressure by a flow of liquid in said system, and a gage actuable bv the subatmospheric pressure thus created for indicating conditions existing in said system.

3. T he combination with a liquid-circulating' system, of common means for inducing a How of liquidpin said syste-1n and for creating' a sub-atmospheric pressure, and a gager actuable by the sub-atmospheric pressure thus created for indicating conditions existing in said system.

In testimony whereof I affix my signature.

JAMEs Eastman 

